Various as-harvested fruits and vegetables are processed by drying the raw produce to yield a dried agricultural product. For example, grapes are dried to yield raisins, plums are dried to yield prunes, and so on. The oldest and perhaps most common method of drying produce is to set out the produce in sunlight until the produce has sufficiently dried. Using the sun as the heat source for drying produce is an energy efficient technique, but not an especially fast or reliable one.
One improvement over sun-drying has been the development of drying ovens, especially those built on a commercial scale. Such drying ovens include a heat source for directly or indirectly supplying heat or hot air to produce to quickly remove moisture therefrom. While fast and relatively efficient, these systems consume fuel to produce the heat and consequently also generate waste heat. Further, the application of heat to the produce must be carefully controlled to avoid damage from overheating.
Raw produce can be damaged from even a mild application of heat, which immediately begins to degrade vitamins, nutrients and flavor. Food products that have not been previously exposed to elevated temperatures retain their aesthetic and nutritional value, even when dried.
Current produce dehydration systems suffer from the disadvantages of high energy costs associated with generating heat for direct or indirect application to the produce. Another disadvantage is that current produce dehydration systems heat the produce in order to dehydrate it, often causing collateral damage to the produce. Another disadvantage associated with current dehydration technology is that the discharged air is known to contain pollutants, such as hydrocarbons, that are harmful to the air quality of the atmosphere. Another pollutant discharged is excess heat itself.
Thus, there is a need for an improved dehydration system for drying raw agricultural producer that reduces the generation of heat and the need for consumption of fuel to achieve the same, as well as a need for reduced expulsion of pollutants into the atmosphere. The present novel technology addresses these needs.